After Mitt Romney, nobody had a worse election than Karl Rove. The “architect” of George W. Bush’s victories, Rove was looked at by many Republicans as even more pivotal this year than Romney. With outside conservative groups raising $1 billion — more than the Romney campaign — Rove was expected to engineer another Republican triumph both in the White House and in the Senate. He himself controlled hundreds of millions of dollars through his two political groups, American Crossroads and Crossroads GPS. Yet not only did his presidential candidate lose, but so did every Senate candidate he backed in a close race.

On election night, he underwent a bizarre meltdown on Fox News and then suffered the even greater humiliation of Donald Trump’s tweeting, “Congrats to KarlRove on blowing $400 million this cycle. Every race CrossroadsGPS ran ads in, the Republicans lost. What a waste of money.” Ouch.

As the GOP grapples with how to move forward and compete in 21st century America, Rove’s example offers useful lessons about what his party did wrong — and what it can still do right.

What won’t work is the strategy he pursued this cycle of bombarding the country with negative ads. According to Kantar Media’s CMAG, which tracks television spending, Rove’s groups spent $127 million on more than 82,000 ads just for Romney, most of them attacking Obama. His House and Senate strategy followed the same playbook. And not only did Democrats win the White House, but they improved their standing in the House and Senate.

This disaster has added poignancy because Rove arrived on the national stage in 2000 intending to bring about a Republican realignment that would last a generation, and most of what he did in the Bush White House was geared toward that end. Twelve years later, that goal seems more distant than ever.

So where should Republicans turn for guidance? They should turn to Rove — not the 2012 vintage, but the guy who elected Bush. A diligent student of history, Rove was always a better analyst than practitioner of big-picture politics, and his analysis a decade ago of where American politics stood and how the parties could prosper — conveyed to me by his protege, Ken Mehlman, who managed Bush’s 2004 campaign — still rings truer than anything I’ve heard since.

“If you look back over the last few decades, an era of politics has run its course,” Mehlman told me at the time. “Both parties achieved some of their highest goals. Democrats got civil rights, women’s rights, the New Deal, and recognition of the need for a cleaner environment. Republicans got the defeat of the Soviet Union, less violent crime, lower tax rates, and welfare reform. The public agrees on this. So the issues now become: How do you deal with the terrorist threat? How do you deal with the retirement of the baby boomers? How do you deliver health care with people changing jobs? How do you make sure America retains its economic strength with the rise of China and India? How that plays out is something we don’t know yet.”

Nearly a decade later, we can see how that is playing out. Democrats have tried to address many of these new concerns, most notably through Obamacare. But the Republican agenda has curdled into something that not only fails to meet these concerns, but seems principally dedicated to undoing the settled battles of the past — rolling back rights for women and minorities, raging against new ones such as health care, and espousing an anti-tax fundamentalism that makes all problems harder to address.

What would a modern Republican agenda look like? It would focus on reform, particularly in dealing with today’s huge emerging challenges: housing, the environment, college affordability, job training, and illegal immigration (which Rove, to his credit, pressed for under Bush and couldn’t achieve).

But first, Republicans will have to break with the past. As the conservative writer David Frum puts it in his new e-book, “Why Romney Lost”: “We must emancipate ourselves from prior mistakes and adapt to contemporary realities.” This is what Rove was thinking and talking about 10 years ago — and is what Republicans should be thinking about now.